1. Field of the Invention
The usual treatment of various eye conditions consists of applying doses of appropriate medicaments in aqueous solutions, suspensions or ointments. While such treatments are satisfactory for treating eye conditions where only one or several applications of the medicinal agents are necessary, certain eye conditions require more frequent doses and the treatment is inconvenient to the patient. Recently, it has been proposed to apply the ophthalmically active medicinal agents in a solid form which will completely dissolve in the lacrimal fluid. See Loucas et al., J. of Pharm. Sci., Vol. 61, page 985, June 1972. The shape of the insert is not critical and may be in the form of a disc, oval, rectangle or rod. However, the rod-shaped insert is preferred, for reasons which will be described hereinafter.
The present invention relates to a mechanical ophthalmic instrument for eye therapy and more particularly to a mechanical instrument for inserting solid medicaments into the cul-de-sac or fornix of the eye.
The cul-de-sac or fornix of the eye is the vaultlike space from the eyelid to the eyeball, bounded by the conjuctiva, the delicate membrane that lines the eyelids and covers the exposed surface of the eyeball. There is, thus, a fornix behind both the lower eyelid and the upper eyelid, and these are termed the inferior conjuctival fornix and the superior conjuctival fornix, respectively.
2. Description of the Prior Art
The ophthalmic applicator device of the present invention is characterized by both safety and reliability. These characteristics are traceable, largely, to the pliable nature of the entire tip of the device, and to the absence of any moving parts in the device of the present invention. Prior art devices such as the one described in U.S. Pat. No. 3,828,777, which utilizes a minute suction cup, while without moving parts, presents serious problems of reliable release into the cul-de-sac of the eye. Other prior art devices which posses pliable jaws or tabs, such as those described in U.S. Pat Nos. 453,508 and 3,780,735, at the same time require the action of a plunger means for ejecting the medicament from the pliable end. Such devices present serious problems of safety and convenient operation in the environment of the delicate membranes forming the fornices fo the eye.
The ophthalmic applicator device of the present invention also possesses a unique juxtaposition of handle and tip portions to form an interior angle therewith of from about 30.degree. to about 120.degree., which has been found essential to the safety and reliability which characterize the device of the present invention. By contrast, devices disclosed heretofore, such as that described in U.S. Pat. No. 3,863,633, show no appreciation of the importance of this unique configuration of the device of the present invention.